a blog post with an interesting title a couple of weeks ago: "Natural selection reduced diversity on human Y chromosomes." Now I'm sure this is a very interesting article for other reasons, but I'm interested in the title of the article, which talks about "natural selection" "reducing" something in something else.
Natural selection, which is, apparently, some actual thing, is acting on some other thing. This brings up several questions having to do with ontological status of natural selection. What exactly is it? Is it some ghostly force? Is it a mechanism? How can it act on something else? In what way is it a subject that acts on other objects?
And this article title is hardly unique. Many scientists talk this way--in a way that reifies the abstractions they have themselves fashioned.
Now there seem to be two possible views here: First, there is the prescriptive view: that natural selection is a thing--it has some ontological status in the world and that it acts upon other things in the world. Second, and alternatively, there is the descriptive view: natural selection is not a thing in and of itself, but is rather a description of the way the world, in fact, behaves. Another way of putting it is that, under the prescriptive view, natural selection is something in the world, whereas under the descriptive view it is something in the mind of the scientist.
To talk about it in the way this article title does--and in the way many scientists do on many other occasions--assumes the first view. Do these people really believe that natural selection is a thing? Or is this just their careless way of speaking?
I imagine if you corner your scientific friend who speaks in this way, he will finally have to say that it is just a manner of speaking, in which case you can't really say that natural selection does anything.
Maybe, in regard to natural selection, it is just a way of speaking. But there is the same issue in regard to natural laws. Are they real in and of themselves? Do they have some prescriptive force on the things they are said to govern? Or are they simply descriptions constructed to fit a set of facts and events in the world?
I don't think it is too much to say that the general public thinks of things like natural selection and the law of, say, gravity, as things having prescriptive force. And it's partly due to the way scientists are always talking. I suspect that in this case there are more scientists who would take the prescriptive view. And this is certainly the way the layman thinks about scientific laws: that they govern things in the world, making them do this and that and prohibiting them from doing that and the other thing.
That is, after all, what laws in the real sense of laws--the things our legislatures pass--do: they govern things. They order this thing to happen and this other thing not to happen. The whole reason for calling regularities in nature laws is to produce this impression that there is something out there that makes things in nature act a particular way.
The prescriptive view of natural law is wholly unscientific. And by that I mean not that it violates any scientific principle (that would be positing a prescriptive law governing prescriptive laws), but that such a view lies outside the very purview of science. If scientists want to claim to be empirical, then they can't possibly believe in the prescriptive view because the prescriptive view is metaphysical. It is what the philosopher David Hume said about causation in general: it can never be arrived at by any empirical method: Nobody has ever seen a natural law. It is a metaphysical postulate that explains the way things happen. But it is wholly non-empirical.
This, in fact, is the whole objection to miracles: that they are claims that there are events that violate natural laws. The objection to miracles assumes the prescriptive view. And yet, I suspect that a number of the atheists out there who are always championing the integrity of science, and who would admit that, from an empirical standpoint, natural laws are merely descriptive, will turn right around and argue against the miraculous on the grounds that miracles violate prescriptive laws.
As Chesterton pointed out in his "Ethics of Elfland," the only way to view the world prescriptively is to view it as the result of prescriptive will. In fact will is the only thing that can really be prescriptive: It is the necessary condition for prescriptiveness. To use the term "law" in the context of science and then to deny that you are using it prescriptively is try to have your scientistic cake and eat it too. It's either careless or dishonest--or, perhaps more likely, thoughtless.
The way atheistic scientists talk is many times at odds with their stated positions. They say on the one hand that they are not engaging in metaphysics, but as soon as they say that, they render much of what they say unintelligible. Their very denials make gibberish of the truths they affirm.
It's one of the great ironies of the whole language of science and natural law (or for that matter natural selection) that it only makes sense from a position of theism.